The personhood of the Holy Spirit is clearly affirmed in the
Fourth Gospel where Jesus says, "The Holy Spirit, whom the Father
will send in my name, He will teach you all things" (John
14:26), and thereafter adds that "the Spirit of truth, who proceeds
from the Father, He will bear witness to Me" (15:26).
Note that personal pronouns are used in regard to the Holy Spirit.

There are many other references in the New Testament that depict
the Holy Spirit functioning as a person. A few may be mentioned:
"The Holy Spirit said, 'Set apart for Me Barnabas and Saul for
the work to which I have called them'" (Acts 13:2); "the Spirit
Himself intercedes for us" (Romans 8:26); "do not grieve the
Holy Spirit of God" (Ephesians 4:30); and "the Spirit and the
Bride say, 'Come'" (Revelation 22:17). There are many other
similar references portray the Holy Spirit as a person.

Hence it is important not to think of the Holy Spirit
as merely an attribute of God, such as power. There are passages
that might suggest the Spirit to be God's power in creation
(e.g., Genesis 1:2), or in regeneration (e.g., John 3:5), or
at Pentecost where the Holy Spirit is promised and the disciples
receive power for their witness and ministry (Acts 1-2). The
fact that they were "filled with the Holy Spirit" (Acts 2:4;
cf. 4:31) might sound more like being filled with energy than
with a person. However, in all these instances the important
thing to recognize is not that the Spirit equals power, but
that where the Spirit of God is there is power. Moreover, we
are to understand that to be "filled with the Holy Spirit" is
not simply to be filled with a substance or force but to be
fully possessed by the Holy Spirit, the personal Spirit of God.

In the spiritual (or "charismatic") renewal of our time, one
of the most outstanding testimonies is that of how real and
personal the Holy Spirit has become to many individuals. Thus,
deepening Christian experience marvelously confirms the biblical
record (see Renewal
Theology, 1: chapter 4, "The Holy Trinity").